Hypothesis: One potential explanation for a given fact or observation
If you have already derived really good questions and narrowed your focus to one of those questions, the next step in the scientific method is a lot easier. If your question is broad, it's harder. (Example of a broad question: Why are there so many types of animals?) Hypotheses abound--
There are so many types of animals because:
1) there are many types of niches available for organisms to exploit;
2) the more types there are, the more lineages are available to split and diversify further;
3) natural selection has pushed species in different evolutionary directions at different times and places;
4) sexual selection has lead to random exaggeration in features in the absence of strong natural selection;
5) natural and sexual selection have worked in concert to shape species features in different ways at different times; etc.
In this example, there are a number of different levels and perspectives to approach this problem. This makes it difficult to derive one set of mutually exclusive (only one hypothesis can be supported at a time), testable hypotheses. However, if we have a more focused question, the hypotheses are easier to derive. (Example of a focused question: Do more complex ecosystems have greater biodiversity?) Here I refer to complexity in terms of temperature and precipitation profiles, number of trophic levels (e.g. plants vs herbivores vs carnivores), and variability of habitat. In this case, the hypotheses, or possible answers to this question, are more obvious--
In this example, there are a number of different levels and perspectives to approach this problem. This makes it difficult to derive one set of mutually exclusive (only one hypothesis can be supported at a time), testable hypotheses. However, if we have a more focused question, the hypotheses are easier to derive. (Example of a focused question: Do more complex ecosystems have greater biodiversity?) Here I refer to complexity in terms of temperature and precipitation profiles, number of trophic levels (e.g. plants vs herbivores vs carnivores), and variability of habitat. In this case, the hypotheses, or possible answers to this question, are more obvious--
More complex ecosystems:
1) have greater biodiversity because they have more available niches to support more organisms;
2) have equal biodiversity because niche availability does not limit diversity;
3) have less biodiversity because only a few types of generalist organisms can occupy complex ecosystems; or
4) complexity of an ecosystem does not have a predictable effect on biodiversity.
These hypotheses are all mutually exclusive (you cannot have greater biodiversity while having less biodiversity) and they are testable (you can measure the number of species in ecosystems at various levels of complexity, from hot springs to tundra, to rain forest and look for any trends.)
For my own question (Does divergent sexual selection reduce hybridization between subspecies in sympatry?), my hypotheses would be:
For my own question (Does divergent sexual selection reduce hybridization between subspecies in sympatry?), my hypotheses would be:
1) divergent sexual selection (different types of mate preference) reduces interbreeding when subspecies come into contact;
2) divergent sexual selection does not reduce interbreeding when subspecies come into contact;
3) in some cases it does and sometimes it doesn't, depending on the strength and direction of selection.
*Note that in some cases, such as this, some hypotheses may not be mutually exclusive. We can only do the best we can with the information provided and future studies and experiments may lead to clearer distinctions between these possibilities.
Moral of the story--choose a good topic, focus your question and hypotheses are easy.
Cool link of the day: High speed video of a trap-jaw ant attacking a plastic wall and being thrown back, flipping high in the air.
Next--> Current Work
*Note that in some cases, such as this, some hypotheses may not be mutually exclusive. We can only do the best we can with the information provided and future studies and experiments may lead to clearer distinctions between these possibilities.
Moral of the story--choose a good topic, focus your question and hypotheses are easy.
Cool link of the day: High speed video of a trap-jaw ant attacking a plastic wall and being thrown back, flipping high in the air.
Next--> Current Work
